10 Things You Should Know Before Replacing Your Central AC System

Cost Savings Environment

Maybe your old central air conditioner has quit working, and you think you need a replacement.  Maybe you want to upgrade to a more energy-efficient or environmentally-friendly system. Maybe you’re not sure what to do.

Whatever the reason you’re considering a new air conditioner or furnace, you’ll want to go through this handy checklist to make sure you are shopping for the right equipment and asking contractors the right questions.

1.  How much time do I really have to replace my system?

Click here to learn how to put time on your side to get the right equipment for your needs.

2.  Do I really need to replace my entire system or can it be repaired?

Click here to see the many factors facing the repair vs. replace decision.

3.  How much space am I trying to cool (and has it changed since the old AC was installed)?

Click here to learn how you might need more or less cooling and heating power based on changes in your home or workspace.

4.  Do I want something more than “just cold air”?

Click here to read about how improvements in comfort, energy costs and the environment can make you feel better and save you money.

5.   Do I really need to cool the whole house all the time?

Click here to see how some common suggestions can actually lead to bigger problems.

6.  Is there really anything new in air conditioning?

Click here for an overview of new technologies available today and what they mean to you.

7.  Are there unique needs in my region of the country?

Click here to see how where you live might determine the type of equipment you should buy.

8.  Should I replace my furnace if I replace my air conditioner?

Click here to learn how your air conditioner and furnace work together… and apart.

9.  Should I invest in a programmable thermostat?

Click here to see how you can save 20-30% on your energy bill without changing your routine.

10.  How do I know which contractor to hire?

Click here for insights into how to ask the right questions and select the best contractor for your situation.

Was this helpful?

Vote This Post Up 49 Loading...

23 thoughts on “10 Things You Should Know Before Replacing Your Central AC System

  1. What about refrigerants? ie r22 and so on? How do I know that they’re being properly disposed of when I go out and get a new AC unit?

    • Most HVAC contractors know they should not just “vent” old refrigerant to the atmosphere and now there is even more incentive for them to “reclaim” the old refrigerant because the old R22 refrigerant is not being made for sale in the US anymore so if you want to use it for replacement/recharging on an old R22 system you need to “reclaim” it from other old systems. Consequently the price has gone up so there are incentives for contractors to capture the old refrigerant when they do a replacements. I hope this helps. BTW, there are some articles on this site about refrigerants – you can use the keyword search tool. Thanks for visiting our site!

  2. I have a question: An AC repairman quoted a price of $1148 to install a drain flood safety switch and replace receptor contacts on my air conditioning unit. It is located in the attic of my home. This seems terribly high and beyond my budget.

    Is there a less expensive way to take care of these two items and how do I know that I’m not being taken for a ride?

  3. It is difficult to comment on prices for a particular job without knowing the specifics and our policy on this site is not to comment on prices anyway. However, this site does recommend getting quotes or opinions on your particular solution from at least 3 differecnt qualified contractors before you make your HVAC investment decisions. This is especially true on problem jobs or expensive ones.

  4. I have a Ge air conditioner its blows out very cold air, however it is making a loud noise. Any suggestions about what it could be.

  5. I have a window AC unit that needs to be recharged. Can I buy the freon someplace and do this myself? If so, where can I find the freon kit?

  6. I want to install a centrally controlled unit to regulate the 6 individual rooms in my house. This unit should be able to separately control the temperature of each room as well as when to turn on and off the existing heaters. Is it possible? What is the cost estimate to install such unit?

    • Hi Anthony. There are several ways to centrally control individual rooms. If you already have a ducted system (or room for new ductwork) you can install a central HVAC system with automatic duct controls that regulate the amount of conditioned air that goes into each room and this can be done with centralized control. If you use this method I would recommend getting a system with at least two steps of capacity control to allow you maintain effective temperature and humidity control in both a smaller space (many rooms closed off) or the larger space (all open). If you are planning for wide capacity variations you might be better off with a fully variable speed system which allows for that sort of capacity demand flexibility.

      Another way to achieve room by room control is with ductless mini-splits or “mulit-split” systems. However, these units are usually limited to about three separate indoor evaporator units (mounted on the walls in the space to be cooled). With this arrangement you would only have three separately controlled spaces – not six. You could install two units with three each but I do not think you would not have centralized control on all six rooms unless they have come up with a way to link them together to a central controller.

      A third way to achieve six separate zones is with ductless variable refrigerant flow system (VRF) that can handle multiple room evaporators with one, central outdoor unit. These units are used mostly in commercial buildings in the US but are also available for residential applications as well. Our research has shown that these systems tend to be more expensive than either ductless multi-splits or ducted, central HVAC systems.

      There is a lot of information in the articles and posts on this site that deal with the tradeoffs of these systems so you might want to spend some time with that material. We usually recommend getting at least 3 quotes from qualified HVAC contractors for each of the systems you are considering before deciding on a new system since some of these businesses tend to specialize in one or the other. Also, depending on the climate in your area you might want to talk to the contractors about issues related to humidity control, air flow, air filtration, winter heating, and other factors which can be affected by the type of system you choose. Our policies on this site do not allow us to recommend any particular brand of equipment or service provider but you can probably perform an internet search on some of the system types mentioned above to do more research. Good luck with your HVAC project!

  7. Hi, the heating coil (replacement quoted at $1400) on my HVAC unit is cracked & needs replacing. We replaced the circuit board about 2yrs ago as well. So we are faced with replacing the whole unit ($4200 total for a Payne unit) or just the coil.

    We live in Greenville, SC & plan to move in the next year…so we don’t know which is a better decision; replace the part & wish the new owner the best or replace the whole unit & advertise that when selling our house & try to get the money back in the sale of the house? The house is in the $115,000 range, and it’s roughly 1600 sq ft. The unit that is breaking down is about 10-12yrs old.

    Also, should we look into geothermal units because of the tax breaks? Are there any tax breaks for replacing a HVAC unit? Sorry for all the questions, but we’re (like most people) in a pretty tight spot financially. Thank u

  8. Hi Jon – Here are a few thoughts. Our recent survey data indicates that on average, US consumers replace their HVAC systems when they are about 14 to 16 years old depending on where you are located and how many hours it runs each year (i.e. shorter life for a heat pump in the south running year round). So, at 10 to 12 years old, your system could be coming up on its useful life expectancy. Reasons for replacing it could also include likely energy savings as you upgrade to the new minimum efficiency standards as well as an upgrade to the latest refrigerant (if you have R22 now it might be more difficult to repair your old unit in the future as that refrigerant is being phased out by the EPA). This would be in addition to the home selling feature of having a brand new HVAC system.

    You could also be seeing some utility and other state/local rebates for going with a higher efficiency model than just the minimum, which is now 14 SEER in SC. One site we recommend for checking rebates is http://www.dsireusa.org/ and your contractor should be able to help you with this as well.

    On the geothermal option, the payback could be a little longer than you are expecting even after the rebates but the energy savings can be significant so it might be worth considering. In any case, we usually recommend getting 2-3 quotes from different contractors for each system type before deciding. Good luck with your HVAC project!

  9. Iam having my old furnace and ac replaced its from 1998.My new furnace and ac are being installed today.But my contractor is using my old copper lines for the ac?Should he replace them or wash them out .Before he hooks it up?

    • You can ask to have the copper lines replaced but it will probably cost more especially if they are difficult to access. The risk from not replacing them is basically leaks – probably at the braze joints or bends. If you keep the old lines they should be cleaned and flushed before recharging with new refrigerant. You should probably ask the contractor about this.

  10. I just had a new heating/air conditioning unit replace a day ago; should the tech have replaced the heating coil at the same time? He said that it may have to be replaced at a later if needed. If this is a brand new installation, should everything have been replaced. He left no instructions in writing,nor did he show me the manual. When he left, I found the instruction packet in the yard. When installing the new unit, is the refrigerant included in the entire package? Last question, should he have asked me if I wanted to keep the old unit to scrap it or do they normally take it with them?

    • Hi Beverly – Here are my thoughts on your questions. It sounds like you have a heat pump system (that also works like an air conditioner in the summer) and had the outdoor unit replaced and did not replace the old indoor coil and air handler. My answers assume that is the case – if something else was done, please provide a little more information and I will try to answer later.

      It is fairly common to replace just the outdoor unit of an air conditioner or heat pump and leave the indoor coil and air handler if it is functioning ok and not too old. As long as your old and new unit used the same refrigerant there should not be a problem. If the refrigerant in the new outdoor unit was upgraded to a different refrigerant then there are a few additional steps that need to be done by the contractor but that approach is still pretty common as well.

      If he just changed the outdoor unit there should not be any change in the way you operate your system – it should work the same as before but reading the instructions and keeping them handy would be a good thing to do.

      Refrigerant charging or re-charging would probably have been included in the service charge as the system would not run without it.

      Most contractors include disposal of your old unit in the cost of the job unless you tell them you want to keep it for some reason. Most people just let the contractors take care of the disposal process. Some scrap dealers want the parts separated into various components – copper, steel, aluminum, etc and if you take it to a scrap dealer yourself they might not accept it – plus you have to haul it there and all. Most people just let the contractor handle it. I hope this answers your questions.

      • I hate when they take it without asking. Are you telling me they charge to take it? I hope not they should give a discount for taking it cuz its worth money

        • Hi Kato – You can ask a contractor about that but again, it is often not easy for a person to get it to the scrap dealer and sometimes the dealers charge because it has all the metals mixed up and they have to tear them apart to separate. It is always good to ask though. The contractor should be able to explain your options.

  11. My home and AC unit are almost 8 years old. My home has 2 units 1 each for upstairs and downstairs. I’ve already had to replace the coil on the upstairs unit (900.00) and now i”ve been told that on the reversing valve is stuck in the middle and my unit needs to be replaced. Is this normal, so early in the life of an AC? Of course my home warranty doesn’t cover valves.

  12. Hi Wanda – Our homeowner research suggests that the typical, U.S. style central AC systems are replaced when they are, on average about 14 years old. This age can vary due to climate and run times i.e. units in the south and heat pumps get replaced sooner due to longer run times experienced in each season. Repairs for an 8 year old system are not uncommon but you might ask the contractor if you can just replace the reversing valve instead of the whole outdoor unit. We also recommend getting 2-3 quotes from different contractors before deciding. I hope this helps to answer some of your questions.

    • Hi Gloria – depending on the size of the coil, your location and the other parts you might need to change this could cost between ~$1,000 and $1,500+ for material and labor to install. We also recommend getting 2-3 quotes from different contractors before deciding. I hope this helps to answer some of your questions.

Leave a Reply

Your email address will not be published. Required fields are marked *